The Matron answered the front door to find her friendly postal carrier there with a package (a book, of course).
As she was thanking him the harmless deaf-blind geriatric dog stood at her side and barked non-stop. Satan's Familiar went immediately for the man's feet. Did the Matron mention that one of the things Scruffy routinely destroys are shoes? It doesn't matter if you're wearing them, either.
Because Scruffy is barely bigger than an ant and this postal carrier of considerable height and apparently no dog fear, he just gave his foot a little shake and said: "Is that the dog who bites the mail when it's coming through the door slot?"
Matron: "Oh! You can tell. Yes, he always grabs the mail. Big highlight of his day."
Postal carrier: "Yup. He bites my hands too. Here you go. I have a warning card for you."
He handed the Matron a postcard that said this, and was on his way.
Your dog has been biting at mail as it comes through the slot. This is dangerous both for the preservation of your mail and for the physical safety of your mail carrier.
When your mail carrier comes to your home, keep your dog inside, away from the door, in another room or on a leash. Don't allow your dog to bark, jump up against the door, or bite the mail as it comes through the mail slot. Not only is this dangerous for the mail carrier, it will only encourage your dog to attack the letter carrier if met outside or in a yard.
Even Scruffy's single talent spells trouble.